Bobcat 642B won’t rev up

[BumpaDuck]

Greetings all, Newbie here. I overhauled a Mitsubishi 4G32 engine and it won’t rev up. Fires, runs marginally at low rpm’s but will not respond to throttle position. Overhauled the following items: Engine, Carburetor, Distributor, Control Valve, Block Port, Axles, Drive Motors, etc. Plenty of gas getting to carb. Could float be improperly adjusted to make it not allow enough fuel into engine? Thanks for all your help.

 

[Dave1234]

Are you sure the governor and linkage is correct? Maybe try disconnecting the governor and open the throttle by hand at the carburetor? Running marginally doesn't sound right. Is it somehow under load? Can you operate all the hyd systems and they act correct? Jack it up so the wheels are free to turn? Turn the parking brake off? Right control stick not in aux position? Sounds like this is the first time to tred to run it? Sounds like your carb lacks the glass sight window to verify fuel level. Mine was like that. Seemed to run too rich all the time so I wound up fitting a Chinese carb to it from ebay--worked great, but now maybe a little lean for max power. Before that I looked everywhere for carb float setting and could find nothing. You should be able to roughly evaluate carb setting by smelling the exhaust to see if it is way too rich, or makes black smoke, but trying to hit the right setting by guess or by golly won't be fun--I tried.

 

[BumpaDuck]

Are you sure the governor and linkage is correct? Maybe try disconnecting the governor and open the throttle by hand at the carburetor? Running marginally doesn't sound right. Is it somehow under load? Can you operate all the hyd systems and they act correct? Jack it up so the wheels are free to turn? Turn the parking brake off? Right control stick not in aux position? Sounds like this is the first time to tred to run it? Sounds like your carb lacks the glass sight window to verify fuel level. Mine was like that. Seemed to run too rich all the time so I wound up fitting a Chinese carb to it from ebay--worked great, but now maybe a little lean for max power. Before that I looked everywhere for carb float setting and could find nothing. You should be able to roughly evaluate carb setting by smelling the exhaust to see if it is way too rich, or makes black smoke, but trying to hit the right setting by guess or by golly won't be fun--I tried.

I am out off town at the moment. When I get back I will jack it up and see if it will start with wheels off the ground. Yes, it sounds like it is under load. Would I chase the bypass relief valve for under load condition? No sight glass, correct. Appreciate your response.